Variable aspiration control device

ABSTRACT

An aspiration control device may include a conduit having a distal end and a proximal end. The conduit may define a conduit lumen and an aperture vent open to the conduit lumen. A coupling may be configured to couple the proximal end of the conduit with a vacuum source and an inner cannula of a tissue cutting device. The inner cannula may define an inner cannula lumen wherein the vacuum source is configured to supply a vacuum to each of the coupling lumen and the inner cannula lumen. A sleeve may be movably disposed about the conduit, and a device motor may be in communication with the sleeve and be configured to move the sleeve to a predefined position relative to the vent in response to an input single from a user interface. The predefined position of the sleeve may correspond to a predefined level of vacuum to be supplied to the inner cannula lumen.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation-in-part of U.S. application Ser. No.13/628,972 filed Sep. 27, 2012, now published as U.S. 2014/0088526, thedisclosure of which is hereby incorporated in its entirety by referenceherein.

TECHNICAL FIELD

The present disclosure relates to surgical devices, in particular,surgical devices that perform multiple functions and that are suited forneurosurgical and spinal surgical procedures.

BACKGROUND

Various abnormalities of the neurological system, such as brain andspinal tumors, cysts, lesions, or neural hematomas, can cause severehealth risks to patients afflicted by them, including deterioration inmotor skills, nausea or vomiting, memory or communication problems,behavioral changes, headaches, or seizures. In certain cases, resectionof abnormal tissue masses is required. However, given the complexity andimportance of the neurological system, such neurosurgical procedures areextremely delicate and must be executed with great precision and care.

Traditional tissue removal systems such as suction cannula, shavers andultrasonic aspiration system have a predefined level of aspiration orvacuum delivered to the tip of the device. This predefined level ofvacuum is usually defined by a vacuum source and may be eithercompletely turned on or completely turned off. Some systems attempt tosupply levels of vacuum somewhere in between the on and offconfiguration by creating a bleed hole for the vacuum supply that allowsa portion of the vacuum to be bleed out of the inner cannula, thusreducing the level of vacuum supplied to the tip. A user may elect tocover a portion of the bleed hole by using the user's fingertip to coverall or a portion of the hole. By allowing the hole to be covered, only aportion of the vacuum supply is bleed through the hole, thus creating alevel of vacuum less than the vacuum supplied by the vacuum source.However, this technique does not allow for a variable, reproduciblelevel of vacuum.

Other tissue removal systems employ peristaltic systems. In peristalticsystems, a pump is set to a specific speed to generate vacuum. However,hysteresis that peristaltic systems exhibit provide difficulties toachieve instantaneous flow changes. For example, peristaltic pumps lackthe ability to immediately vent vacuum pressure from a peristaltic pumpsystem to atmosphere. Accordingly, when it becomes desirable to releasetissue from a surgical device, for example when the instrument comesinto contact with a critical structure, the operation of the peristalticpump is not capable of immediately responding to a vent input. Instead,the operator is required to wait until the pump can adjust and necessaryequilibrium of the system is restored. Such actions may result insurgeon fatigue during a surgical action, as well as potential damage totissue where it is necessary to immediately release tissue.

Peristaltic pumps often also exhibit a pulsed flow, particularly at lowrotational speeds of the peristaltic pump. Thus, peristaltic pumps areless suitable where a smooth consistent flow is required.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of an exemplary tissue cutting device.

FIG. 2 is a cross-sectional view of the tissue cutting device of FIG. 1.

FIG. 3 is a partial cross-sectional view of a distal region of the outercannula and inner cannula of the tissue cutting device of FIG. 1,depicting the inner cannula in a first relative position with respect tothe outer cannula.

FIG. 4 is a partial cross-sectional view of a distal region of the outercannula and inner cannula of the tissue cutting device of FIG. 1,depicting the inner cannula in a second relative position with respectto the outer cannula.

FIG. 5 is a perspective view of an exemplary aspiration control deviceof the tissue cutting device of FIG. 1.

FIG. 6 is a partial top plan view of a portion of the aspiration controldevice of FIG. 5.

FIGS. 7A-D are partial top plan views of a portion of exemplaryconfigurations of the conduit of the aspiration control device of FIG.6.

FIGS. 8A-C are partial top plan views of a portion of exemplaryconfigurations of the sleeve of the aspiration control device of FIG. 6.

FIG. 9 is a tissue cutting system employing an exemplary aspirationcutting device for an aspiration control device.

FIG. 10 is an exemplary control system for the exemplary aspirationcontrol device.

FIG. 11 is a partial top plan view of a portion of another exemplaryaspiration control device.

FIG. 12 is an exemplary tissue cutting system employing the exemplaryaspiration cutting device of FIG. 11 at a first location within thetissue cutting system.

FIG. 13 is an exemplary tissue cutting system employing the exemplaryaspiration cutting device of FIG. 11 at another location within thetissue cutting system.

FIG. 14 is an exemplary tissue cutting system employing the exemplaryaspiration cutting device of FIG. 11 at another location within thetissue cutting system.

FIG. 15 is an exemplary tissue cutting system employing the exemplaryaspiration cutting device of FIG. 11 at another location within thetissue cutting system.

FIG. 16 is an exemplary tissue cutting system employing the exemplaryaspiration cutting device of FIG. 11 at another location within thetissue cutting system.

DETAILED DESCRIPTION

Described herein is a tissue cutting device that is suited forneurosurgical applications such as the removal of spine and braintissue. The cutting device is configured to connect to an existingvacuum supply, which may include a vacuum system hose fluidly connectedto an existing vacuum source in a wall of a surgical room. The vacuumsupply may supply a predefined level of vacuum to a tip of an innercannula lumen of the cutting device. The tissue cutting device may beconfigured to include an aspiration control device configured to controlthe level of vacuum supplied to the tip. The control device may have aconduit defining an aperture vent and a sleeve encompassing the conduit.The sleeve may be configured to move with respect to the conduit inorder to expose various portions of the vent. The level of vacuumapplied to an inner cannula lumen may be controlled by a handpiece or afoot pedal by exposing various portions of the vent. Accordingly, theaspiration control device may control the level of vacuum in a steady,fixed and repeatable manner.

While described herein in the context of a tissue cutting device, itunderstood that the principles of the disclosure may be employed with avariety of other surgical devices. Examples of such surgical devicesinclude, but are not limited to, rotary shavers, reciprocating cuttingdevices, ultrasonic aspirators, and ablative technology instruments.

Referring to FIGS. 1 and 2, an exemplary tissue cutting device 10includes a handpiece 12, an inner cannula 56 (best seen in FIGS. 3 and4) and an outer cannula 22. In one exemplary embodiment, the handpiece12 may be configured to be generally cylindrical in shape as well assized and shaped to be grasped with a signal hand. The handpiece 12includes a lower housing 14 which comprises a proximal section 16 and adistal section 18. A tissue collector 20 may be operatively connected tothe upper housing 24. While shown attached directly to the upper housing24, it is understood that the tissue collector 20 may be positionedremote from the upper housing 24. (See, e.g., FIG. 9.) The upper housing24 may include a lower shell 26 and an upper shell 28 disposed above thelower shell 26. An aspiration control device 30 may be configured tocontrol the level of vacuum within an inner cannula 56 of the tissuecutting device 10. The aspiration control device 30 may include aretainer 32 disposed on the upper shell 28 of the upper housing 24 thatis configured to hold an aspiration device conduit 34. The retainer 32may be secured by an adhesive or other manner. The aspiration deviceconduit 34 may be connected at a coupling 36 to the vacuum system hose38. A hose connector 40 may also be provided. Hose connector 40 mayprovide a mechanism for securing a vacuum system hose 38 to thehandpiece 12 to prevent accidental dislodgement of the vacuum systemhose 38 during operation. A rotational dial 44 for rotating the outercannula 22 with respect to the handpiece 12 may also be mounted to theupper housing 24.

As best seen in FIGS. 3 and 4, the outer cannula 22 includes an openproximal end (not shown), a closed distal end 52, and a tissue receivingopening 54. As discussed above, the tissue cutting device 10 furtherincludes the inner cannula 56, which is partially disposed in an outercannula lumen 58. The inner cannula 56 is configured to reciprocatewithin the outer cannula lumen 58 and to cut tissue samples 72 enteringthe outer cannula 22 via the outer cannula tissue receiving opening 54.The inner cannula 56 reciprocates between a distal position, which isdepicted in FIG. 3, and a proximal position, which is depicted in FIG.4. The distal end 62 may be configured to cut tissue, as describedherein. Inner cannula distal end 62 may also be beveled in a radiallyinward direction to create a sharp circular tip and facilitate tissuecutting. A motor 70 (shown in FIG. 2) may be disposed in the lowerhousing 14 of the handpiece 12 and be operably connected to the innercannula 56 to drive the reciprocation of the inner cannula 56 within theouter cannula lumen 58. The motor 70 may be a reciprocating or rotarymotor. In addition, it may be electric or hydraulic. The outer cannula22 and the inner cannula 56 may be made of materials that are generallyrigid, such as rigid plastics or metal. In one example, both cannulaeare constructed of stainless steel, such as 304SS typically used inmedical grade instruments.

In operation of the tissue cutting device 10, as the inner cannula 56translates in the distal direction, it contacts tissue received in thetissue receiving opening 54 and the received tissue is severed andaspirated in the proximal direction along the inner cannula lumen 60 andreceived in the tissue collector 20. Thus, the inner cannula lumen 60provides an aspiration path from the inner cannula distal end 62 to theinner cannula proximal end 64.

The tissue receiving opening 54 may have a number of shapes. In certainexamples, when the tissue receiving opening 54 is viewed in plan, it hasa shape that is generally square, rectangular, trapezoidal, ovular, orin the shape of the letter “D”. In certain other exemplaryimplementations, the tissue receiving opening 54 is configured to directtissue that it may be compressed as the inner cannula 56 translates inthe distal direction.

As discussed above, the tissue collector 20 may be located remotely fromthe handpiece 12 and outside the sterile field during a tissue cuttingoperation (See FIG. 9.) Alternatively, as shown in FIGS. 1 and 3, tissuecollector 20 may be removably connected to the handpiece 12. The tissuecollector 20 may be connected to the upper housing 24 proximally of theinner cannula 56 to receive the aspirated tissue samples 72. In anexemplary arrangement, the tissue collector 20 may be generallycylindrical and hollow and have an interior valve that is in fluidcommunication with the inner cannula lumen 60 and a source of a vacuum,such as the vacuum system hose 38, is operably connected to the tissuecollector 20 to direct samples into the tissue collector 20. The tissuecollector 20 may be removably secured from the tissue cutting device.For example, in the exemplary arrangement shown, the tissue collector 20may be removably secured to the upper housing 24 to allow for theperiodic removal of collected tissue samples 72. It may be sealed to theupper housing 24 in a manner that provides a substantially leak-proofvacuum seal to maintain consistent aspiration of several tissue samples72. The tissue collector 20 may also include a cylindrical cap 46 havinga hollow interior for receiving a portion of the tissue collector 20 (asseen in FIG. 9.) The cap 46 may be fluidly connected to the vacuumsystem hose 38 and permit the tissue collector 20 to be removablyattached to the hose 38 at the cap 46. A vacuum hose fitting 74 may beformed on the proximal end of the tissue collector 20 and be in fluidcommunication with the interior of the tissue collector 20 and with thevacuum system hose 38.

Referring to FIGS. 5 and 6, aspiration control device 30 is described infurther detail. Aspiration control device 30 may include an optionalretainer 32, control device conduit 34 and a sleeve 80. The conduit 34may define a conduit lumen 86 and have a conduit proximal end 82 and aconduit distal end 84. Further, because the aspiration control device 30may be an add-on mechanism for existing handpieces, the aspirationcontrol device 30 may need to be operably attached thereto. The retainer32 may be secure the conduit 34 of the control device 30 at the distalend 84 to the upper housing 24 (as shown in FIG. 1) via an adhesive orother manner to prevent the conduit 34 from being displaced relative tothe handpiece 12. The proximal end 82 may be configured to be receivedby the coupling 36. The coupling 36 may form a three-way union betweenthe vacuum system hose 38, the inner cannula 56 and the conduit lumen86. The coupling 36 may form a T-like shape whereby the proximal end 82(as best seen in FIG. 5) of the conduit 34 may be inserted into one ofthe three openings in the coupling 36.

The sleeve 80 may be disposed around at least a portion of the conduit34. As shown in FIG. 5, the sleeve 80 may be disposed around the conduit34 between the retainer 32 and the coupling 36. Alternatively, thesleeve 80 may be disposed between conduit distal end 84 and the retainer32.

A control device motor 88 and a driver 90 (as best seen in FIG. 2) maybe in communication with the sleeve 80 and be configured to control themovement of the sleeve 80 in response to a user input from a userinterface 92, e.g., pedal. (See, e.g., FIG. 9.) The control device motor88 and the driver 90 may be housed in a motor housing 94. The driver 90may be used to convert the rotational motion of motor 88 into thetranslational motion of the sleeve 80. The control device motor 88 maybe a reciprocating or rotatory motor operably connected to the sleeve 80to drive the reciprocation of the sleeve 80 over the conduit 34, asindicated by line A in FIG. 6. In additional, the motor 88 may beelectric or hydraulic. The motor 88 may also be a linear motorconfigured to move the sleeve 80 linearly about the conduit 34, asindicated by line B. A linear motor may move the sleeve 80 in distal andproximal directions along the conduit 34, allowing the sleeve 80 tocover, all, none or a portion of vent 100, to be discussed in greaterdetail below. In one exemplary arrangement, the motor 88 may be abrushed DC motor. As shown and described in more detail with respect toFIG. 9, the user interface 92 may be connected to the motor 88 and thedriver 90 via an input line 96. The input line 96 may carry anelectrical signal from the user interface 92 to a control 98 disposed atand in communication with the motor 88.

As explained, the conduit 34 includes an aspiration vent 100. The sleeve80 surrounds at least a portion of the conduit 34 and includes a sleevebody 106 and a sleeve tip 108. The sleeve tip 108 may be formed of avariety of shapes, as shown by way of example in FIG. 8. The vent 100may also be defined by a variety of shapes, as shown by way of examplein FIGS. 7A-D. As the sleeve 80 moves with respect to the conduit 34, sodoes the location of the sleeve tip 108 with respect to the vent 100.For example, as shown in FIG. 6, the sleeve tip 108 may cover a portionof the vent 100.

The coupling 36 facilitates a vacuum supply of vacuum to each of theconduit lumen 36 and the inner cannula lumen 60. In other words, thevacuum supplied by the vacuum system hose 38 is split between the twolumens via the coupling 36. When the vent 100 is uncovered, the suppliedvacuum may be vented from the conduit 34 through the vent 100.Alternatively, when the vent 100 is closed by the sleeve tip 108, noneof the supplied vacuum may be vented. Thus, as the vent 100 is closed,the level of vacuum supplied to the inner cannula lumen 60 is at itsfull level. That is to say, the vacuum previously applied to the conduitlumen 36 is redirected to the inner cannula lumen 60.

Accordingly, by closing the vent 100 with the sleeve 80 so that thesleeve tip 108 covers the entire the vent 100, the supplied vacuum inthe conduit lumen 36 is eliminated. By eliminating the vacuum within theconduit lumen 36, the entirety of the vacuum supply is forced on theinner cannula lumen 60. Alternatively, when the vent 100 is not coveredby the sleeve 80, at least a portion of the vacuum is vented from theconduit lumen 36 via the vent 100. Thus, by increasing the amount ofvacuum vented by the conduit lumen 36, the vacuum of the inner cannulalumen 60 is decreased. The vacuum in the conduit lumen 36 may be totallyeliminated or totally enabled, as described above. The vacuum level mayalso be varied by exposing a portion of the vent 100, as shown in FIG.6. The sleeve 80 may be moved via the driver 90 and control device motor88. The sleeve tip 108 may have a plurality of predefined positions,such that, depending on the user input at the user interface 92, apre-established vacuum supply may be administered to the inner cannulalumen 60.

More specifically, the user's actuation and change in the position ofthe user interface 92 is defined by the user's observation of thetissue's response to the current aspiration level of the vacuum supplyand the user's desired outcome and effect on the tissue and surroundingstructures. For example, in certain situations, the user may desire toreduce the aspiration level of the vacuum supply to hold and move tissueaway from critical structures, rather than having the aspiration levelof the vacuum supply pull tissue within the tissue cutting device 10 andsever tissue samples.

Indeed, by implementing the system above, a repeatable and variablelevel of vacuum may be supplied to the inner cannula lumen 60 based onthe position of the sleeve tip 108 relative to the vent 100. Thus, auser may apply a different level of vacuum at various times of aprocedure. For example, some surgical procedures require the removal ofunwanted tissues from critical structures such as neurovascularstructures and brain tissue. It is important that the user have absolutecontrol over the level of vacuum applied to various areas affected bythe procedure at the tissue receiving opening 54 or tip. If an unwantedmass is being removed during the surgical procedure, a high level ofvacuum may be required to remove the mass. Additionally oralternatively, a lower level of vacuum be appropriate when suctioningportions of the mass that are in close proximity to critical structures,such as brain mass or other nervous system tissues.

FIGS. 7A-D show a plurality of alternative vent 100 configurations. Thevent 100 may be formed of a rectangular shape, as shown in FIG. 6.Alternatively, the vent 100 may be formed of an oblong or oval shape, atriangular shape, or any other shape that could be covered by the sleevetip 108. FIGS. 8A-C show a plurality of alternative sleeve tip 108configurations. For example, the sleeve tip 108 may include an angledtip 108, as shown in FIG. 6. Alternatively, the sleeve tip 108 mayinclude a triangular tip 108, rectangular tip 108, or any other shapedtip 108 capable of covering the vent 100, in a known and predictablemanner.

FIG. 9 is an exemplary implementation of a tissue cutting systemconfigured to supply variable levels of vacuum to the inner cannulalumen 60. For example, the system may include cutting device 10, tissuecollector 20, vacuum system hose 38, vacuum source 114, control devicemotor 88 and control 98. As discussed above, the tissue collector 20 maybe located remotely from the handpiece 12 and may be placed far enoughfrom the handpiece 12 to remain outside of the sterile field during atissue cutting operation. The vacuum system hose 38 a connects cap 46 ofthe tissue collector 20 to the coupling 36. A fluid canister 116 may beconnected to the tissue collector 20 via the system hose 38 b and to thevacuum source 114 via the system hose 38 c. Thus, vacuum source 114 isin fluid communication with the tissue collector 20 and the innercannula lumen 60, thereby generating a vacuum at the proximal end ofinner cannula 64 to aspirate severed tissue samples 72 from the innercannula distal end 62 to the tissue collector 20. Via the coupling 36,the vacuum source 114 is also in fluid communication with the conduitlumen 36 of aspiration control device 30. The level of vacuum applied tothe inner cannula lumen 60 is variable and selectively controlled by theuser via the user interface 92. Vacuum levels from about 0 to 29 in. Hg.may be applied, with a vacuum level of about 29 in. Hg. being mostpreferred. Lower levels of vacuum may be desired around criticalstructures, e.g., as the user moves into the critical zone of amicro-dissection phase of a cytoreduction operation. Higher aspirationlevels are desirable as the user is in a gross debulking phase of thecytoreduction operation.

The sleeve 80 provides a mechanism for continuously adjusting andcontrolling the level of vacuum applied to the inner cannula lumen 60based on a user's individual need, regardless of the vacuum levelavailable from the vacuum source. The control 98 may receive and providesignals to the various components of the aspiration control device 30.It may provide signals to motor 88 and the sleeve 80 via an input line96 extending from the control 98 to the sleeve 80. These signals areused to control the rotation or linear movement of the sleeve 80 inresponse to a desired level of vacuum. The control 98 receives signalsfrom the user interface 92 via the input line 96. Thus, the control 98provides immediate feedback to the motor 88 and the driver 90 which canin turn provide signals to the sleeve 80.

The user may adjust the level of vacuum by varying settings, or controlson the user interface 92. In one example, the user interface 92 is apedal, specifically a foot pedal. In one example, the foot pedal may bedepressed and configured to activate the control device motor 88. Inexchange, the sleeve 80 may be rotated to a predetermined positiondepending on the amount of depression of the pedal. As pedal isdepressed, the sleeve 80 is moved to apply a minimum level to a maximumlevel of vacuum. Foot pedal may provide continuous movement betweenfully open and fully depressed positions which in turn correspond to aplurality of vacuum levels that may be supplied to the inner cannulalumen 60. The user may also select from a plurality of intermediatepositions available between fully open and fully depressed. Thesepositions may correspond to a level of vacuum somewhere between theminimum level and maximum level.

The user interface 92, e.g., pedal, may be connected to control 98 viaan electrical input. The control 98 may be electrically connected to themotor 88 and the motor 98 may be in communication with the sleeve 80. Avacuum sensor (not shown), which may be a temperature compensatedsolid-state pressure sensor, may be positioned within the inner cannulalumen 60. Alternatively, the vacuum sensor may be placed in the systemhose between the inner cannula 56 and the coupling 36. The sensor may beelectrically connected to the control 98.

FIG. 10 presents an exemplary closed loop control path for automaticcontrol of the vacuum level of the inner cannula lumen 60. In operation,the control 98 is responsive to the input signal provided by the userinterface 92 over the input line 96. The control 98 therefor facilitatesa desired level of vacuum to the inner cannula lumen 60 in response toinput at the user interface 92. The actual vacuum level provided to theinner cannula lumen 60 is sensed by a vacuum sensor, which provides afeedback signal to the vacuum feedback input. The control 98 is thenoperable to compare the vacuum feedback signal with the vacuum commandsignal and correspondingly adjust the position of the sleeve 80 toachieve the desired vacuum level within the inner cannula lumen 60. Morespecifically, a linear actuator or rotary actuator that iselectronically or pneumatically/fluidically controlled may beoperatively connected to the sleeve 80 to move the sleeve appropriatelyas needed for the desired vacuum level. The sleeve 80 could be activelyactuated in both a forward and rearward direction. In yet anotherembodiment, the actuator may be configured to be spring biased so thatactive actuation would only be directed in a single direction, againstthe biasing force of the spring.

In another example, the control 98 may be replaced by individualmicroprocessors controlling the input and output for controlling theoperation of the control device motor 88. These microprocessors may bePIC16CXX Series microcontrollers provided by Microship, Inc. ofChandler, Ariz. The microcontroller can provide output to the control 98and have its own display, such as an LED display, indicative of tisoperational status.

In certain examples, the user may adjust the level of vacuum to achievea desired level of “traction” in the tissue surrounding the tissue to besevered. Traction may refer to the exertion of a pulling force on tissuesurrounding the target tissue to be severed. In some instances, tractionmay be visualizable by the surgeon with the use of a magnificationinstrument, such as a microscope or an endoscope. The level of vacuumwill also determine the amount of unsevered tissue that is drawn intothe tissue receiving opening 54, and therefore, the size of the severedtissue snippets. Therefore, when fine shaving operations re desired, thevacuum level will be relatively lower level than if debulking (largescale tissue removal) is performed. Of course, the pre-selected maximumvacuum level will also affect the maximum size of tissue that is drawninto the tissue receiving opening 54, and therefore, will affect themaximum size of severed tissue samples 72 during any one operation.Also, the vacuum level may be adjusted based on the elasticity, fibroticcontent, and hardness/softness of the tissue. As explained, the variablevacuum level may be achieved by altering the coverage of the vent 100 bythe sleeve 80. Thus, in operation, the larger the desired tissue sample,the more coverage of the vent 100 by the sleeve 80, creating a higherlevel of vacuum.

In another example, the user interface 92 may be a knob used to set apreselected vacuum level. The knob may then activate the device motor88, which may in turn rotate the sleeve 80 to an appropriate positionrelative to the selected vacuum level. A control console may also beused that includes an analog or digital display. The display mayindicate the selected vacuum level.

In the foot pedal example, a user may not need to manually adjust a knobor control interface with his or her hands, allowing for more controland accuracy in guiding the cutting device. Instead, a user may depressthe foot pedal with his or her foot and generates an appropriate vacuumlevel. Control interface may be used in conjunction with the pedal andprovide a display of the current vacuum level. Thus, a user could adjustthe level of vacuum by depressing or lifting the foot pedal in responseto the level displayed via the control console.

As explained, the tissue cutting device 10 may be used to perform acutting operation. However, the tissue cutting device 10 may also beused as an aspiration wand without cutting any tissue, thus operating asa multi-functional surgical device. The tissue cutting device 10 mayalso be used as a blunt dissector whereby the outer cannula 22 may beused to move or manipulate tissue to position tissue for cutting. Morespecifically, when used for tissue manipulation, the outer cannula 22may be manipulated to allow a user to scrape tissue from a structure,such as critical vessels, thereby minimizing or even preventing anydamage to such structures. In one exemplary procedure, the tissuecutting device 10 may be deactivated such that inner cannula 64 stopsmoving. In this configuration, the vent 100 on the outer cannula 22 maybe used as a rake to pull across tissue and rake tissue off criticalstructures and/or vessels. Additionally, the user may vary theaggressiveness of this action by the lack of vacuum being delivered tothe vent 100 or by varying the amount of vacuum being delivered to thevent 100, as well as the amount of downward force applied to the subjecttissues.

In one exemplary configuration, the inner cannula 56 may be deactivatedsuch that a distal end of inner cannula 56 is positioned proximally ofthe tissue receiving opening 54, allowing a user determined level ofvacuum may be supplied to the tissue receiving opening 54. As explained,vacuum may be used to pull tissue away from critical structures suchthat the vacuum supply is used as the retraction mechanism or the tissueholding mechanism in the same way that the introduction of a separatesuction cannula device would be used. Thus, in moving tissue away fromcritical structure, a lower level of vacuum may be necessary than thatrequired to remove a large mass. Moreover, as the procedure isperformed, the user may wish to easily adjust the level of vacuum. Forexample, initially the user may be removing a large mass. However, asthe mass is removed, the tissue receiving opening 54 may become closerand closer to critical structures. As this happens, the user maygradually decrease the level of vacuum to more accurately and carefullyremove tissue in abutting the critical structure.

In another exemplary use, the outer cannula 22 may be used as a vesseltapenade. In this application, the outer cannula 22 may be selectivelypressed on a vessel to assist in providing direct pressure on theoffending vessel to control and stop bleeding, as the outer cannula 22does not generate heat. In yet another use, vacuum may be simultaneouslyapplied to the vent 100 to evacuate the field of the surgical site priorand/or during the use as a tapenade so that the user may be able tovisualize and determine the exact location of the offending vessel thatrequires hemostasis. Furthermore, since the vent 100 is configured onthe side of the outer cannula 22, the distal end of the outer cannula 22or the non-the vent 100 side of the outer cannula 22 may be used as thetapenade, for example.

In another example, vacuum may be used to aspirate fluid from a surgicalsite to clear the field and in conjunction with the tissue cuttingdevice 10 when activated to resect and remove target tissue from thesurgical site. Because the tissue cutting device 10 may be used in avariety of manners, the tissue cutting device 10 also allows flexibilityfor a user to vary his or her approach to each surgical situation. Byusing a foot pedal as the user interface 92, a user may change thevacuum level without use of the user's hands.

FIG. 11 is a partial top plan view of a portion of another exemplaryaspiration control device. Similar to the example shown in FIG. 6, aconduit 34 may define a conduit lumen (not shown in FIG. 11) and a vent100. A sleeve 155 may surround at least a portion of the conduit 34 andmay be configured to selectively cover at least a portion of the vent100 in response to user input at the user interface 92, similar tosleeve 80 as shown in FIG. 6. The sleeve 155 may be included as part ofa sleeve device 150. Moreover, the sleeve 150 may define any of the tipconfigurations shown in FIGS. 8A-8C and the vent 100 may include any ofthe configurations shown in FIGS. 7A-7D.

The sleeve device 150 may include a control device motor 88 and driver90 (not shown in FIG. 11) configured to control the movement of thesleeve 155 in response to the user input. The sleeve 155 may be abobbin-like mechanism configured to move linearly about the conduit 34,as indicated by line B. The sleeve device 150 may house the device motor88 and driver 90. Additionally or alternatively, the motor 88 and driver90 may be housed in a separate housing (not shown in FIG. 11). Asexplained, the control device motor 88 may be a linear motor oractuator, a ball and screw drive, coil and permanent magnet arrangement,etc. configured to move the sleeve 80 linearly about the conduit 34, asindicated by line B. A linear motor, which is controlled by userinterface 92, may move the sleeve 80 in distal and proximal directionsalong the conduit 34, allowing the sleeve 80 to cover, all, none or aportion of vent 100. The control device 30 may be connected eitherdirectly or indirectly to the vacuum source 114 via the hose 38 c toprovide controlled suction to surgical instrument 10.

FIGS. 12-16 are exemplary surgical instruments employing the exemplaryaspiration control device 30 of FIG. 11. The aspiration control device30 may be arranged at various locations along the vacuum system line 38.FIG. 12 illustrates an example where the control device 30 is arrangedbetween the vacuum source 114 and the fluid canister 116 within systemhose 38 c. FIG. 13 illustrates an example where the control device 30 isarranged between the fluid canister 116 and the tissue collector 20 onsystem hose 38 b. FIG. 14 illustrates an example where the controldevice 30 is arranged between the tissue collector 20 and the hoseconnector 40 on system hose 38 a. FIG. 15 illustrates an example wherethe control device 30 is arranged between the hose connector 40 and theupper housing 24 of the handpiece 12. Although not shown, additionalconnectors, spacers and/or supports may be arranged along the hose 38 toprovide additional support for the hose 38. For example, additionalsupports may be arranged along the handpiece and be configured tomaintain the hose 38 along the handpiece during operation.

With respect to the example shown in FIG. 12 where the aspirationcontrol device 30 is placed in line with system hose 38 c, theaspiration control device 30 may be outside of the biological materialpathway. That is, the control device 30 is not susceptible to biologicalcontamination, which may permit the aspiration control 30 to be areusable component. This may also be the case with respect to theexample shown in FIG. 16. The examples show in FIGS. 13-15 may also bereusable. Moreover, the control device 30 may be disposable and may beused in conjunction with a reusable interface or pedal 92.

The control device 30, as explained, may act as a valve to affect thelevel of vacuum on the hose 38 c by exposing various portions of thevent 100 with the sleeve 150. As the vent 100 is closed via the sleeve150, the more suction from the vacuum source 114 is supplied to the hose38 c. Conversely, as the vent 100 is uncovered, the more suction fromthe vacuum source 114 is bleed through the vent, decreasing the suctionsupplied to the hose 38 c.

FIG. 16 illustrates another arrangement of the control device 30 wherethe control device 30 may be arranged at the system host 38 c. In thisconfiguration, the control device 30 may be arranged on a separate tube160 that forms a T-junction with the hose 38 c. A distal end 165 of thetube may be closed. The control device 30 may, similar to the examplesabove, affect the level of vacuum on the hose 38 c by exposing andclosing the vent 100 in response to interaction at the interface 92.Moreover, although the arrangement is shown by way of example in FIG. 16to be arranged at the system hose 38 c, the control device 30 may alsobe arranged in a t-like arrangement anywhere along the aspirationpathway, including at any one of the other system hoses 38 a and 38 b.

As mentioned, the control device 30 may be arranged outside the sterilefield during a tissue cutting operation. In addition to the device 30being reusable, the device may also be used in connection with existingvacuum devices without modifying the vacuum device. That is, the controldevice 30 may be used with existing cutting devices and vacuum suppliesas an add-on component without further modifications to those devices.

Accordingly, the aspiration control device may be arranged at variouspositions along the vacuum system hose and may be configured to controlthe pressure drop delivered to the surgical instrument in response touser input at the user interface.

It will be appreciated that the surgical device/tissue cutting devicesand methods described herein have broad applications. The foregoingembodiments were chosen and described in order to illustrate principlesof the methods and apparatuses as well as some practical applications.The preceding description enables others skilled in the art to utilizemethods and apparatuses in various embodiments and with variousmodifications as are suited to the particular use contemplated. Inaccordance with the provisions of the patent statutes, the principlesand modes of operation of this invention have been explained andillustrated in exemplary embodiments.

It is intended that the scope of the present methods and apparatuses bedefined by the following claims. However, it must be understood thatthis invention may be practiced otherwise than is specifically explainedand illustrated without departing from its spirit or scope. It should beunderstood by those skilled in the art that various alternatives to theembodiments described herein may be employed in practicing the claimswithout departing from the spirit and scope as defined in the followingclaims. The scope of the invention should be determined, not withreference to the above description, but should instead be determinedwith reference to the appended claims, along with the full scope ofequivalents to which such claims are entitled. It is anticipated andintended that future developments will occur in the arts discussedherein, and that the disclosed systems and methods will be incorporatedinto such future examples. Furthermore, all terms used in the claims areintended to be given their broadest reasonable constructions and theirordinary meanings as understood by those skilled in the art unless anexplicit indication to the contrary is made herein. In particular, useof the singular articles such as “a,” “the,” “said,” etc. should be readto recite one or more of the indicated elements unless a claim recitesan explicit limitation to the contrary. It is intended that thefollowing claims define the scope of the invention and that the methodand apparatus within the scope of these claims and their equivalents becovered thereby. In sum, it should be understood that the invention iscapable of modification and variation and is limited only by thefollowing claims.

What is claimed is:
 1. A tissue cutting device, comprising: anaspiration control device arranged between a vacuum source and a fluidcanister and having a conduit defining a conduit lumen and a vent thatis open to the conduit lumen, a sleeve slidably disposed about theconduit, and a device motor in communication with the sleeve andconfigured to move the sleeve relative to the vent in response to aninput signal from a user interface, wherein the position of the sleeverelative to the vent provides for a desired vacuum level within theconduit, wherein a predefined position of the sleeve corresponds to apredefined level of vacuum to be supplied to an inner cannula lumen. 2.The device according to claim 1, wherein the sleeve has a sleeve bodyand a sleeve tip extending from a distal end of the sleeve body, the tipbeing configured to cover at least a portion of the vent.
 3. The deviceaccording to claim 2, wherein the motor is configured to drive thesleeve longitudinally along the conduit to place the sleeve tip in apredefined position relative to the vent.
 4. The device of claim 1,wherein the predefined position of the sleeve corresponds to adepression position of the user interface.
 5. The device of claim 1,further comprising a tube forming a T-junction with a vacuum hosebetween the vacuum source and tissue collector, wherein the conduit isarranged on the tube.
 6. The device of claim 5, wherein the tubeincludes a closed distal end.
 7. A tissue cutting device, comprising: anaspiration control device having a conduit defining a vent and a sleeveslidably disposed about the conduit and configured to move with respectto the vent, a device motor in communication with the sleeve andconfigured to move the sleeve relative to the vent in response to aninput signal from a user interface, wherein a predefined position of thesleeve corresponds to a predefined level of vacuum to be supplied to aninner cannula lumen.
 8. The device of claim 7, wherein the aspirationcontrol device is arranged between a vacuum source and a fluid canister.9. The device of claim 7, wherein the aspiration control device isarranged between a fluid canister and a tissue collector.
 10. The deviceof claim 7, wherein the aspiration control device is arranged between atissue collector and a handpiece of the tissue cutting device.
 11. Atissue cutting device, comprising: an aspiration control device arrangedbetween a vacuum source and a fluid canister and having a conduitdefining a conduit lumen and a vent that is open to the conduit lumen, asleeve slidably disposed about the conduit, a device motor incommunication with the sleeve and configured to move the sleeve relativeto the vent in response to an input signal from a user interface,wherein the position of the sleeve relative to the vent provides for adesired vacuum level within the conduit, and a tube forming a T-junctionwith a vacuum hose between the vacuum source and fluid canister, whereinthe conduit is arranged on the tube.